Currently, a number of different types of devices are available for monitoring human subjects in a non-invasive manner. For example, heart function and respiration can be monitored in a patient through the use of electrodes which must be attached to the skin of the patient. Although non-invasive, such equipment is nevertheless uncomfortable for the patient, who must remain still while being monitored and who is attached to a network of sensors. In addition, such equipment is very expensive, limiting its use to hospitals and other medical settings in which both the cost and the discomfort of the patient can be justified. Furthermore, patients may become anxious when examined by medical personnel, thereby significantly altering the normal readings for these patients.
However, there are many different situations in which non-invasive monitoring of a human subject is desired. For example, such monitoring could be very useful as part of the overall health maintenance of the human subject, and could be used in order to detect a deterioration in the physiological condition of the subject before a concomitant deterioration in the health of the subject becomes noticeable. Examples of adverse physiological conditions which could be detected with regular non-invasive monitoring include but are not limited to excessive weight gain or less; arrhythmia and other heart conditions; incipient diabetes in the form of improper glucose metabolism; and loss of lung capacity or other problems with respiration.
In order to support regular monitoring of human subjects in their normal environment, such as in the home and at the office for example, the equipment must be non-invasive and easy to use. The equipment would then be able to monitor at least one physiological parameter of the human subject, without requiring the human subject to perform any complicated actions and/or to operate complex devices. Indeed, it would be highly preferred for the equipment to be incorporated as part of the regular daily living routine of the subject, since the requirement for any additional or special actions on the part of human subject is likely to result in decreased compliance. In addition, the equipment should be robust yet inexpensive. Furthermore, the equipment should be able to analyze data which is collected as part of the monitoring of the physiological parameter, or at least should be able to transmit such data to a remote computational device for analyzing the data. Unfortunately, such equipment is not currently available.